Applications of AU-FDS to High- Concentration Antibody Interactions 3-D Cell Culture Systems: Understanding Interactions and Aiding Research
Back To Podcast Page
Victoria Mosolgo :
Hello everyone, and welcome to the CHI Podcast. This is Victoria Mosolgo, Associate Conference Producer at Cambridge Healthtech Institute. We're here today with Dr. Thomas Laue, Professor of Biochemistry and Molecular Biology, and director of the Biomolecular Interaction Technology Center at the University of New Hampshire. Tom will be giving a keynote presentation at the fifth annual High-Concentration Protein Formulation Conference, part of this year's Bioprocessing Summit taking place August 15th through the 19th in Boston. Tom, welcome, and thank you so much for joining us today.
Tom Laue :
Glad to be here, and I'm looking forward to the meeting in August.
Victoria Mosolgo :
What are the major obstacles in high-concentration protein formulation?
Tom Laue :
Low solubility and high viscosity remain the most significant problems. Being able to foresee these problems during drug discovery phase would lower development costs significantly.
Victoria Mosolgo :
How are you and other people tackling these issues?
Tom Laue :
There's a lot of work on determining the structural features of the protein that lead to poor solubility and high viscosity. Work so far indicates that three factors are important, the net charge, the charge distribution, the presence of hydrophobic patches. Ongoing work is focused on ways to evaluate and use metrics that are based on measurements of these three properties. While it would be useful to be able to predict values from sequence or structure, doing so remains elusive at this time.
Victoria Mosolgo :
Can you share with us how AUF-DS is useful for high-concentration interactions?
Tom Laue :
AUFDS observes the sedimentation of a fluorescently-labeled molecule. The label acts as a reporter on the interactions of that molecule with other unlabeled molecules. The results are presented as a size distribution, since the sedimentation coefficient is the ratio of the buoyant molar mass to the frictional coefficient. The result has real physical meaning. The label could be held at a fixed concentration, or you can vary the concentration of the label, but you may obtain data from solutions of any concentration of unlabeled background molecules. AUF-DS is used to monitor a labeled molecule in high concentration of itself, to be self-interactions, or high concentration of other antibodies, hetero-associations. It could even be used in complex mixtures of molecules like serum, sputum, urine, cerebral spinal fluid. Furthermore, the size distribution of its complexes with an antigen may be observed in complex concentrated solutions.
Victoria Mosolgo :
We see that you'll be delving more into this topic in your upcoming keynote on August 18th. What can the audience expect from that talk?
Tom Laue :
Well, lots of examples. There are going to be cases where the AUF-DS has been used to reveal unanticipated interactions at high concentrations, unanticipated interactions in serum, for example. There are going to be examples of instances where the size distribution of the antibody-antigen complex are very different in buffer from what you actually observe in serum. Finally, there will be a situation where only AUFDS is capable of demonstrating a medically-relevant interaction in serum.
Victoria Mosolgo :
Why have you chosen to present at the fifth annual High-Concentration Protein Formulation Conference.
Tom Laue :
I love coming to these conferences because I learn so much about protein chemistry high concentration fluids, and important practical applications of knowing more about them. Some of the best protein solution chemists attend these conferences, and I always get a thrill from learning from them. Finally, it's a wonderful opportunity to chat with old friends, and to make new acquaintances.
Victoria Mosolgo :
My last question for you is are there any particular speaker or talks that you're looking forward to this year?
Tom Laue :
There are a number of them. I'm looking forward to Atul Saluja's talk relating surface content probabilities to aggregation. The talk fits in with this ongoing desire to predict solubility on a basis of structure. The other talk is in my session by Danny Chou, looking for early seed aggregation, controlling downstream problems, and Shantanu Sule on the impact of charged isomers on aggregation also look very interesting. Finally, I'm interested in knowing whether Mark Gang's observation of pH shifts with protein concentration are dominant effects or whether buffer binding is involved. There are other sessions that look really interesting as well. Claudia Mueller's talk, for example, on formulation of protein hits on an important question: What additional challenges might be anticipated for making mixtures of proteins?
Victoria Mosolgo :
Tom, thanks a lot for speaking with us today. I look forward to meeting you in Boston.
Tom Laue :
Take care.
Victoria Mosolgo :
Again, that was Dr. Thomas Laue. Tom will be giving a keynote presentation at the fifth annual High-Concentration Protein Formulation Conference, running August 18th through the 19th in Boston as part of this year's Bioprocessing Summit. For more information on the Bioprocessing Summit, please visit our website, Bioprocessingsummit.com. My name's Victoria Mosolgo. Thanks for listening. We hope to see you in August.